A deadly crackdown on opposition demonstrators appeared tonight to have punctured the most serious protest movement in Iran since the 1979 revolution, as an eerie quiet settled on Tehran and the regime turned its attention to more familiar enemies overseas.

Protesters who have shaken the authorities by venting anger en masse at the "stolen" elections that returned Mahmoud Ahmadinejad to office spoke of a hiatus, even a despair, settling on the movement after yesterday'sSaturday's clashes killed at least 10 and wounded scores more. State television blamed the casualties on clashes between police and "terrorist groups".

Tonight, sporadic gunfire was heard in northern parts of Tehran, yet there was no repeat of the mass protests that have brought hundreds of thousands to the streets of the capital in the last week.

Foreign affairs columnist Simon Tisdall on the weekend's events in Iran and the country's relations with the west Link to this audio

Some opposition figures were still hoping that their figurehead, the defeated presidential candidate Mir Hossein Mousavi, would emerge tomorrow to lead another rally calling for the elections to be annulled. But Saturday's crackdown, in which police wielded guns, truncheons, tear gas and water cannon, showed that the state intends to follow through on veiled threats of zero tolerance from the supreme leader, Ayatollah Ali Khamenei.

Mousavi issued an elliptical statement today in which he spoke of a "turning point" being "forged in the history of our nation. People are asking each other and also me, when among them, what should be done and in which direction we should go," he said. But he stopped short of giving a clear answer. "Protesting against lies and fraud [in the election] is your [Iranians] right," the statement said. "In your protests, continue to show restraint. I am expecting the armed forces to avoid irreversible damage," he added.

There has been another wave of arrests, with reports today of the detention of five female relatives of Hashemi Rafsanjani, a former president widely seen as the orchestrator of the opposition movement. Dozens of journalists have also been detained; yesterday it was reported that Maziar Bahari, a filmmaker and Newsweek correspondent, had been arrested.

The regime also turned its attention to more distant adversaries, with Ahmadinejad blaming the US and Britain for the crisis. "Definitely by hasty remarks you will not be placed in the circle of friendship with the Iranian nation," he was quoted as saying about the countries in a meeting with clerics and scholars. "I advise you to correct your interfering stances."

The foreign minister, Manouchehr Mottatki, told foreign diplomats in Tehran today that Iran had faced "an in-flooding of British intelligence officials ahead of the election". Britain's foreign secretary, David Miliband, replied: "I reject categorically the idea that the protesters are manipulated by foreign countries."

Germany's chancellor, Angela Merkel, urged Iran not only to allow peaceful protests but to conduct a recount of votes cast in the election. "Germany is on the side of the Iranian people, who want to exercise their rights of freedom of expression and free assembly," she said. France's foreign minister, Bernard Kouchner, called the crackdown a "brutal repression". Italy's foreign minister, Franco Frattini, expressed similar sentiments but confirmed that Iran was still invited to discuss Afghanistan and Iraq at a conference in Trieste this week.

Barack Obama did not expand today on earlier comments in which he called on the regime "to stop all violent and unjust actions against its own people".

Those actions took on a new dimension on Saturday as the security forces responded to a directive by Khamenei to enforce official bans on all public protests. Demonstrators spoke of a surreal atmosphere on the streets, in which the euphoria of solidarity and resistance mingled with adrenalin, smoke and fear.

Amateur video showed the demonstrators pelting police with stones and shouting: "Death to the dictator."

Scores of injured protesters who sought medical treatment were arrested by security forces at hospitals in the capital, the International Campaign for Human Rights in Iran claimed. The organisation said doctors had been ordered to report protest-related injuries to the authorities, and some seriously injured protesters had sought refuge at foreign embassies.

Violence also spread to other cities, including Shiraz, where police were said to have lashed out at members of the public who were not involved in protests.

Mohammad Khatami, a former president and another leader of the reformist camp, spoke out against the repression. "The provocative and insulting portrayal of our people – accusing their healthy civil protest to be an act of foreign influence – is an example of the wrong policies that further distance people from our government," he said. "A massive number of people do not believe the [election] results. Public trust has been damaged and closing the door to civil protests means opening a dangerous path, and God knows where that will lead."

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